Malicious PDF — malware analysis report

Static analysis result for SHA-256 753595494e4523d9…

MALICIOUS

PDF

79.7 KB Created: 2021-09-20 03:50:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 299ce09e3735ab334bdd987e3175342a SHA-1: b4b50c35491417b37c151af930e8bce622ee4d50 SHA-256: 753595494e4523d9b11ccc32b43468e7b525c92df482aef611d4755a44b1598d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier with high confidence. It contains an embedded JavaScript stream and a large number of external URIs, many of which are hosted on compromised WordPress sites or disposable domains, indicating a phishing or spam lure. The embedded JavaScript likely facilitates the redirection to these malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://pixomot.ru/uplcv?utm_term=change+bluetooth+codec+android
    • http://thsport.dk/userfiles/file/defidajikomawovop.pdf
    • http://progettogeometra.it/userfiles/files/monuvesakidisidilururix.pdf
    • https://interconformity.ro/images/file/setumesemomewerori.pdf
    • https://www.mediawerf.nl/bundles/store24backoffice/ckfinder/userfiles/files/74923139469.pdf
    • https://uat-tunisia.com/userfiles/file/zibigun.pdf
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161348a93f3c7b---lerimivipogobozewe.pdf
    • https://www.vibrationmonitoring.asia/wp-content/plugins/formcraft/file-upload/server/content/files/16146611d0938a---lorepuzo.pdf
    • https://emotionalgift.youngzonejewelry.com/ckfinder/userfiles/files/retewofisozig.pdf
    • http://mamnonhieutrung.edu.vn/ckfinder/userfiles/files/46433099617.pdf
    • https://baust.edu.bd/app/webroot/ckfinder/userfiles/files/77215089664.pdf
    • https://promenade-perpignan.com/userfiles/file/kosivuzonixodanoxiba.pdf
    • http://home-plast.ru/foto/files/nifujopedejuxisaded.pdf
    • http://ahzycw.com/upload_fck/file/2021-9-13/20210913021327144697.pdf
    • http://groupkaishan.com/d/files/51886416976.pdf
    • http://pietrek.com/MARCUS/files/file/gegelabaxap.pdf
    • http://alde-pace.org/ckfinder/userfiles/files/77858913876.pdf
    • https://ukmalayalamnews.com/userfiles/file/dipuni.pdf
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16135cce61e87b---63673644049.pdf
    • https://chokysitohang.com/Uploads/userfiles/files/fevaganesoxe.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16139bf0429ab1---21052271682.pdf
    • https://hcs1000.org/wp-content/plugins/super-forms/uploads/php/files/50298f53a9ca4d86ce39fe3586164927/31223515509.pdf
    • http://winhazel.com/indigo/ckfinder/userfiles/files/17119517689.pdf
    • http://kurumakaitori-one.com/js/upload/files/ligikerowuxal.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d44b.bin
cc097644fe6819ad6fbf12dfbab8c3847d0f8c3c217ab3524dee69961173d39d
pdf-font-stream PDF embedded font (sfnt) at offset 0xD44B 16960 bytes
font_01_sfnt_off00010096.bin
5dacd67d73225d0a68f1a646a853970d873299f19d0ab92d6f5410742de9b80c
pdf-font-stream PDF embedded font (sfnt) at offset 0x10096 10752 bytes
font_02_sfnt_off00011903.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11903 16792 bytes